Identification of mutations in channelopsin variants having improved light sensitivity and methods of use thereof

Abstract

The invention provides compositions and kits including at least one nucleic acid or polypeptide molecule encoding for a mutant CoChop protein. Methods of the invention include administering a composition comprising a mutant CoChop to a subject to preserve, improve, or restore phototransduction. Preferably, the compositions and methods of the invention are provided to a subject having impaired vision, thereby restoring vision to normal levels.

What is claimed is: 
     
       1. An isolated polypeptide comprising the amino acid sequence of any one of SEQ ID NOs: 3-10. 
     
     
       2. A cell comprising the polypeptide of  claim 1 . 
     
     
       3. The cell of  claim 2  wherein the cell is in vitro, ex vivo or in vivo. 
     
     
       4. The cell of  claim 2 , wherein the cell is a photoreceptor, a bipolar cell, a rod bipolar cell, an ON-type cone bipolar cell, a retinal ganglion cell, a photosensitive retinal ganglion cell, a horizontal cell, an amacrine cell, or an AII amacrine cell. 
     
     
       5. A method of changing the conductivity of a membrane comprising
 a. expressing in a host membrane the polypeptide of  claim 1 ; and 
 b. contacting the polypeptide with a light under suitable conditions to change the conductivity of the host membrane. 
 
     
     
       6. The method of  claim 5 , wherein the host membrane is a cell membrane of a neuronal cell, a nervous system cell, a cardiac cell, a circulatory cell, a visual system cell, or an auditory system cell. 
     
     
       7. An isolated nucleic acid molecule that encodes for a polypeptide comprising the amino acid sequence of any one of SEQ ID NOs: 3-10, wherein the nucleic acid sequence is operably linked to a promoter sequence. 
     
     
       8. A cell comprising the isolated nucleic acid molecule of  claim 7 . 
     
     
       9. A composition comprising the isolated nucleic acid molecule of  claim 7 . 
     
     
       10. A vector comprising the isolated nucleic acid molecule of  claim 7 .